It is known that DNAs responsible for storage of genetic information and RNAs having various functions as transcripts of DNAs interact with biomolecules such as proteins, various small organic molecules, saccharide compounds, metal ions, and the like. As the saccharide compounds that can interact with DNAs and RNAs, for example, the following compounds are known. Most of these compounds bind to a nucleic acid molecule as an intercalator where an aromatic ring in the molecule is inserted between base pairs of a DNA double-stranded nucleic acid or a DNA/RNA double-stranded nucleic acid.

Saccharide derivatives include aminoglycoside antibiotics such as neamine and neomycin B mentioned above, of which functional group deriving from saccharide primarily participates in binding with nucleic acids. These molecules were known for a long time to site-specifically bind to bacterial 16S rRNA. Recently, it has been revealed that they interact with various RNAs such as the Tat region and Rev region of HIV, and RNA double helices. Further, X-ray crystallography of aminoglycosides suggests that amino group and hydroxyl group of aminoglycosides interact with a phosphate moiety and a base moiety of a nucleic acid (Science, 274, pp. 1367-1371, 1996; J. Mol. Biol., 277, pp. 347-362, 1998; Angew. Chem. Int. ed., 47, pp. 4110-4113, 2008).
It has recently been suggested that oligo-2,6-diamino-2,6-deoxy-α-glucopyranosides having an α-glycosidic linkage may bind to a DNA double-stranded nucleic acid (89th Annual Convention of Chemical Society of Japan, Subject number 2C6-03, Abstract was published on the WEB site on Mar. 13, 2008). As for these oligo-diaminosaccharide compounds, it has been suggested that they are expected to have a strong interaction with the negative charge of the phosphate moieties in both ends of the DNA at binding to a major groove, because they have amino groups at both ends of the molecule and the amino groups are protonated under a physiological condition to form a dication, and that they can easily form a curved structure, which is entropically advantageous at binding to a DNA major groove, because they have a structure in which all of the saccharides are linked via α-glycosidic linkages. However, only up to an intermediate compound in the synthetic route of trisaccharide was actually reported as synthesis thereof. Further, any experimental results as for interactions of these compounds with DNAs were not reported, and the report fails to teach or suggest whether the compounds have affinity also to an RNA double-stranded nucleic acid or a DNA/RNA double-stranded nucleic acid.